SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd04421b764bb8512d078a8403191e4bf715902573a4b00fdd969cccd3dee8f1e' 
  AND token = 'yz8IjAuCaQJNORCXwmECrNXuyOjy32EKMgdkho0+jVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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