SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'a006fac5e397fc9146c141a0cc2edaa138626e221719ad135789d05e324656ab' 
  AND token = 'Y8mvRTT0VY43gpFRwChxcfhzhojjPB6fXe7OS3/7o3Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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