SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e868767fb6ee69501061519e8bfa0a6b4723db157e1478740a959014ad8120f' 
  AND token = 'hJbtipcP38dog+EYg/8Pt3jPasrh2NTzhSzqc4g3qzU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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