SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5151c181ee132bdd733d96964e4a6eeeb45542fbf4d88971629bcf29db6faae' 
  AND token = 'lx+Ov32cxdVDqO+6ZaxV/8zfKjuMpqJD5BqxWmMonBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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