SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92e66b4e8ca90aa56c130e90fbbfa7f356f94bbe9d302021dc5ac5b3cc733f7a' 
  AND token = 'HJz2BabxibZImAAHJmFG18Zu5ANqeikZcXBc+KWIwc8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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