SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65bc0935fd5f741a92bc4b1fde59cd7e5ededb849716cc15886b22bc08885345' 
  AND token = 'lcvVW7FlKkLx0JCoVj05w/7ueKHXZRiVNDO88ft3hIs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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