SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c264c827014420a14dc6e016f58b4b1505bf492583b59d204f364be933eefa5' 
  AND token = '8kh+XgHK7TFlcNDooKYXH5UFfjFLCgTPVINCMl4jeZk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}