SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5614df334f456bb44f9c259ace73cafb78bf625bfdde818e3fd927a69e5fd01f' 
  AND token = 'wqvDOMfVfeW2w7UskdfATRpK+CiXxfW4xZoPdzy3a6g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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