SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '325f97478508f616c367d03d284a790ddd3eb8b42128e08fd9e34d8fa3a7390b' 
  AND token = 'vPWMUjZNRu/VHJw7XKgXBsBHY6+PZbpJtt9Xweo1CJM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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