SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '73f2dc4194b1d0da6c778e77a3a2a7d9c898b21f8dd3829654a5f60815c145c0' 
  AND token = 'EWIYkbAf1KRyIpAd4jRQfO6GT/LYGX5qAzAGHD6ViVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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