SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62b613a83a49a738f8313eda3b6bacb413b4639d1bacf5ffd6a96467a116d29d' 
  AND token = 'hw/49QR66OtBaqbM+27RFaVdBm4IaYTQwfQJvquAZ4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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