SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efa9316e16d1b0877590f5d31aa2d1ee9db2a380c54908a663a3c43e4d043b76' 
  AND token = 'jYNTlKylHhJHXd88xSxQYE/gTBftBONj9jWRVUZXX4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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