SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd3bc4a18205dfd499ac328c5f41ad9cbe8bf1595c1d750b5e2c16223ff544e7' 
  AND token = 'gqYRoKUUJphItC8V3HkG/u8m5+FNxdpX/7H368cIi1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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