SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdddba1145eecdacdc9b541cd50d0f11ed92f84de44d899afdd0149f4d2c4157' 
  AND token = 'ntMXftz8VGhNAdcixXXdUAqzf+swmMPAj6rJ/BWS2E4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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