SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db5cb10356ec0790b1c44dcc54e12118330d3c8be993323bd08a9efcd73b0814' 
  AND token = 'MoMx4RxiQyyn5IZVWexEx4hxwkraGEfJ06FooGX/7gk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00124

JSON explain

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