SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4119d5f1e4e35b989f5d56fbe63d807145887762502ccdc929cb91892e28e6da' 
  AND token = 'QApyMjYr11LDmGwq6Jc+V4H9kfJZIF2wBHQdI9UUC2M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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