SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2834f37c0915ae1bc995a173acfb8e0df89de58a97eb5c4473c7ae34362ead28' 
  AND token = 'wk6ccCBYMr0dxQCGUDolzpfy/24HgVuUQ3yDrbwVnTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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