SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6081cc962d668b1d60f701fd87a6440f1589781af96c2c8291f73ac2c0bcf3ae' 
  AND token = 'cs1eY66i5KaF97k8P0jhMh8jpt0yWDYRflZ/tjV0wPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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