SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'a84d9f5727378483470cf5f5f3ec350fcc95e175288fb6e387f2385e13cfaf84' 
  AND token = '5rOU0t6cU41jhijWCy9IJtm7Hvk4fthO5u9CnI3kkqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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