SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9c3433f534e42c53cbda59a1dcc356c14598645a9da33c6d258c35b7c8b8d32' 
  AND token = 'bwQRtjXUCmsLQlO/CVEHXDTL0vblQMSJ+4M3rxgV6QI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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