SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd904a3ca1973359c004b24df5177cfb2b673b20ef7e7ed4521f72bbf6cbd75f7' 
  AND token = 'qfztZsP/pnYv0f8QWdqWhdJZGO6nMEhpln00x5xyQQY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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