SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '245728d9e21e8150dd7d524f9cbad1ecadc8353f81a6aa2298999be10a25fa96' 
  AND token = 'iuZjgAuHOY7iBm/hQ+hFhABMEc/FyAZKSX6X3eExztc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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