SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '806fc281609f921cb2323097c893316a3ea322f4214749b73e66622259657324' 
  AND token = 'ZbQyl9vNaZ00OKUyqxON23mq+MkPjgz3lLwZCPqzX6g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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