SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b295e1ac4f43442c5dbef129fa0c44a951b439043e3ed4c4f82ed8ad670b87b7' 
  AND token = 'qBXcUJ8aTiUlsbl5BxxlIncvVL4KKcuhIt3lDJ/ac6Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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