Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97b5a18fb928ad27e0e510d1092d9d0828ac8f25bf0a072a4dfe2fb97f9959aa' 
  AND token = 'VPE4xz+hirs1NDmFJHFtBl3iTHx363q4Dx+1Tnqg/PE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}