SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4656d01526ed4e218e7566199255d83c980dd3c7074b70eb98ef3f3b7a70bcdf' 
  AND token = 'KFYJi8F6GcBnZlr6D/VDwJVznKJVkcrXbqqE0zDYzH8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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