SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '022a783172ca6cc4648ee513f830fbd6683e46032930f79ac5cfe1fa5708e198' 
  AND token = 'RYSn4aLNjqzO7ABQ2FRfuUlBHKmoLvnmu2U6q9GdOGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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