SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4f0cfb80903515afa94084e73cd5a43dbfcf5ad77b67ef15e0664d557ebfd32' 
  AND token = 'JK+ffU2G+nl4YizqiQGwXTUjQAuOUM0/pCtTOlFzaHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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