SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '295679c9d0ff75ef77711127ef52f62243346e82eb67be82cdab6436568d3815' 
  AND token = 'wMGu+VLXYQ652whJlzGFqWLbfV3EtEshUtmb9WxWW+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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