SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82865efddaa95a84fdef5969d97656a37c78da1262baf2f318ea357788ce7a33' 
  AND token = 'MZrRzAmlFTib2AN2bexXZ0GvRPcXRJ4+cZEp0apzFcI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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