SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'eefe80e24a219e756e31dbf012aeb56dc467dde1b40be9a18c6034f26cbf9d58' 
  AND token = 'WaU0QGK5TEgzmNflN9FLjfKGOrU0Y1zjXA0qlZI+mJE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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