SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c6be62c5430dd148112f0891b8e0e37cd61eec067b93602d8cf7cd6d8ea46f3' 
  AND token = 'nm78RC1nAGXD8Ud63lqzSKgyr55xlH8Y/fIpdZqWJwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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