SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db5816d9341bc6c8e4f81758032a4b8b9605fbfa8f0249980cf08c112a09a060' 
  AND token = 'iz4xqQJUKqLKapvvzHymTM4uOWP3Z1cckTQzRPX7AqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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