SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abddd86d27af88a1d8a4d319de51b6d722fcbc4af478439f23ccfa3f7077c663' 
  AND token = 'VAOv0HZSS+9eKnUtaWYEgGgVrQKQvXmWTkWxnc/QJoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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