SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f25a3ce7d09ba2ccf0f3ef27c0666d71aeb07139aaa3578a7bdb4a005716e33' 
  AND token = 'ZMGB3mAVMyX6wjgLiHO/nWkFY9hI6kgFI+lDZRSjOnU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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