Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b7c7c80d910b9c35700ef5eba15723bd467a5a7ebff59d9d40db9cba474ff9a4' 
  AND token = 'Y/K7JF+wbJBkgJ75dMkMaxdcoJc/mUyZ20Q5whadstY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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