Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '519294e3568b5cfb91f31d1a5184fe3bb87c681d5f57bd6618cec2a5875f93c7' 
  AND token = 'u3Lxr8pS8UvIW4OxZCIxMqr+hq1rkRRH+Iohw8w8aBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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