SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd28a1b0c0594f3a521bb8ba46f89a6351270207f2ca7e5b4eb5678751e5e8da0' 
  AND token = 'YUI18ND5kpDWD1wUBjF/yYovV829/M5HxwD8TBuWJPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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