Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '7c3de98f54add7f1d84dce2c2839fea58c188960821e37fe5c6421a00fb2aed1' 
  AND token = 'TT8QEVhDkwmhmzhu2fuEcMT6nqgwgS4NZqdYRPPjcmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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