SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07354e55971bc7cd8e6d684d012cb75098de897988fda2718919f42b8997cc0c' 
  AND token = 'XwfqdEUAnFc6ur9WoYsWSkGWIH3dDih8Wpy+baLYDw8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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