SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7db306fcd105464918ea79a520cf00d69a316beceea9ed61f6847cfbe2195674' 
  AND token = 'KebGia8bGDyeFqUQnk7ISkhZPa3RW7DcPDo6iH55VvA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00059

JSON explain

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