SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2ca0a9da0329b3d076da156eee73a8770e688304883d89304ee1cf071d1a9aa' 
  AND token = 'hBINY/lC+D052rYxZQheykrc5YW+iUWZjkbaf7aQOq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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