SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '84d8b744e819c7d9907f662fe5de158e02b25ecc87d1e62e42ac0ec69b4e32c2' 
  AND token = 'P/KJIcTGQjuVKfgsClIvUSw65sTTsnh+PIkJO5tBjt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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