SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3a29428ab35678a80758026c599c5f10f6133ed1370947e7b99bcc5f3d9c6a2' 
  AND token = 'WXrPffzkPTtptSLCfb2m6FlSD0qfSXEKWgjrC6K7IeE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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