SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0fdec16d9124a64b3a255322ba2c26d6bcaa87f2aa8d235d68c19cff7ce8966' 
  AND token = 'YBCsjayGshgEd8ZC1VbtLUqxfFgRhfTM32N/DtGuIzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}