SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e97db499ca03c6dbc29d6257f7ee306c53ba964e5dc9cd827df01e3519b28d3' 
  AND token = 'g1OXo6jVhG6lWHp9XvEGDgjtGTL/FtRh6HjczKJu14w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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