Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78b4e91a76310a70613a353ac4ae9cc01b9cd92f1a4ccd9caea6cf7f8fa6c477' 
  AND token = 'B8q/KFx6FsbLhVnepwT7lq50W2BxDReR1gfWbPLHCxM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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