SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c420f6c9a79773c216831f2254c6fccb1d07daaf7f2295d42267742af56f3fde' 
  AND token = '8eEaxjgr9hgecQFmg1fMijO8YIBAK/IG5Ke3/f2X2UA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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