SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '958cc003708a893b4a2918ce6663cdd17be47f0a88394bbe6499a56483afa7bb' 
  AND token = '0yHSu8g5UCqgffQuyNOEcIzdP56SfgcfbKTuo5SejgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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