SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0654a1da57b60e9c1c80e36c8dd860b2c45469ee67971f639ec4bad4e95dc11' 
  AND token = 'atZ15Y5pe3ieCimcC453ZqyldKLgvnDtuBskVtCxdz0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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