SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0e95cf8470f4c69ed2f8cf48eb76aa0e79edeeed5b2046ea9f51ba533a67bc76' 
  AND token = 'lYdnH37Z2iLrxOTjesWthDjjSBnFxKD1PDxJ8k2YXpk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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