SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c5742b3fef5fdeadfa5f1c2168b9f48d1a90872745958274acf2aea9e22430c' 
  AND token = 'Bypx++zZvUAT2lzQokcnrCZOzZJm1ECxvQoTicdC8Wg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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