SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b07bcdbd6303b953771306b77ff4b0bf88d4a4e7c995adc6f84217677ec7588' 
  AND token = 'e3KueHc/CnQo+ZuPETxcEBXJwy0YjmjYuKVOVXV3lFc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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