SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63b837618f951615f766cfe6c3c2126cccdbc1e0ef641e39ea0e91ba9eddcb4e' 
  AND token = 'EBcbtW4/ebaj2vGIPekGa30eCnpznst1iJ2ovsToMJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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