SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fcc7128ac3a91f50f49cc6152d44f1e9c5426f2f46b0bb89db0c78d361d98aae' 
  AND token = 'bwwFZ0Dqpe8jjSW+T7FirmZxjWvMWZbCVl/w1tQbvKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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