SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'dde9a02d897e07fb14c1489b6dba3e184c5f9e3c10cdc938226695380f6c97c4' 
  AND token = 'Y/vrFJ91wCO451ReuKmW9f+WbSuGWlhVoIXBtP2Ru3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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