SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbf28269b90b850e09e06b4564378b8cf2f7286146762d23103ab50ca1b6e535' 
  AND token = 'NhHeoej939I+yPibkgPDw5Hxx9kAXKS2RTSte1J244c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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