Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b1cdf5a4f64f0dda02539362d6096c8fda5fb994dcc7bc95e85ccb0be266da5' 
  AND token = 'pqaUlChKSlPX2VCAWAn8JCfyVAeYeraJMqhnZ9Z3lEk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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