SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '213dfda49e4e08bdb5b07c8b927d86586650b18339ae63f63ba1eafcc5b79d44' 
  AND token = 'DPxPOQQGbgtCngcPKHT9pCAY1Y5iRUyhkGOsBTYnu4g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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