SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3a586f7d31a27b3795c71ab9d2b0e582ef6732380dc3ebe8246e117f7908080' 
  AND token = 'gXH7XG5NXCvYHBtWA4rFP/6TKYG/OzXrq+46LIu+3dk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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