SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '150fbae15ea35b9ac65da9475822f311e1b61b51c5f5844068b624e4cd8590c2' 
  AND token = 'gw+uyJjQFQ0FrsHbIsuoGm6oWgdgk0iXIaJ205RLcIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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