SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a92219e4f9fb51a9c890371151bbf3db6acc9090fff04e0e2eae4b8e682cf2b' 
  AND token = 'zRXKS0hv5kNlUo2XoOPol4xm8Lf+xb9GiomXAjb7KZ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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