SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7f3e5365c5b500e86228536a412d456e59bfd1abf0343680e00937032284c064' 
  AND token = '7pdrP+fzsaXXe77Szy56MB6bHfyQxoVMqlJpH9744WY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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