Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e476b751fe646f398d2c53f4d25fa42d115a18408bcd7e06fe669d15bbbfe2b6' 
  AND token = 'b6XZxDaFU0Q6iMgSZ9S3cuVv/wMExzkAmi3ag22pUTQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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