SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a285b627e6299d62e386611b127441308ff9714fc8f9c32fdd05b342bd5bf442' 
  AND token = 'kyz66gGJ1JM0H/NjQxBbo/yWoKfZhkeLWQ3E6SPw+jc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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