SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '7b05db2bdea479ac4674d38ace57546ccb1dc1a47b7713a1571f53399de9b746' 
  AND token = '2/2Sy8V7vMOJW3w9JIfodlKxx/4n4vdQ7cq+KZ8A6mQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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