SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62090818367399c5cdc1a8ecf6f2bf51bd7b7aa92b1dac28c0ab1c74908b0921' 
  AND token = 'EXLmzv5s+hOv7ompXrb84E9GaYjdao3vf11uyuV+Z6I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00123

JSON explain

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