SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c12029034e953ddb418ba8fda4b4398290f389bc152f16e4d0bc9b00b12ee18d' 
  AND token = 'v80Hwpmg/46TqpUPvP2aP4aWIHPlwmeG4v4f8SLHgiM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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