SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd17e11ca481cc70eff2c22a6265153b2b7d583486f2e6f47af4c321cec233680' 
  AND token = 'nPH8tDuTUjo+znYqWCqNEgT9a0JURxLjb01cFESCUuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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