SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ec183b0e924fb76760e35755454183a5a7cfa8c64f6fa1408db43626e849a20' 
  AND token = 'jcGDjm5veNgYO0zIrWjdUUH5gXtw7GwadbusgKqVlKI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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