SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '1d95b47e218c62d34767ff5d4b0d121f3cf90550c50596b1aa76e4af9fc35a3a' 
  AND token = 'Z8eugvipQkki+Xe8J9EdMsWY55mwjhzbcBo/AA9KLss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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