SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58c15652076434ee25b0f3efd11288dc49f825fd40947ff1451ecb4e80ef9cec' 
  AND token = '8vKaneLfnjbS3+syhN0KWtYcxSUyXqsYutsI7e6ROjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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