SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bad5dcac2d06eb590bb288e1bf15b160d72249d4ff9f0120698894b11c513f5a' 
  AND token = 'HYZhODNjBXuRNq0Zv1Khjuz4N1eMztzUCXoGE5J8Uu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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