SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4e34e3a34cdc8238e72a4b36734fd2aded31e5956f107218d891e46cf3405bb' 
  AND token = 'dt6XcikrEJuEEjbyOYwjWIoi/VXTjvgZ6vhfYbJbs1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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