SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '142fab4e3c40229cc5a8dfe70a35b6d7b14f70f6ea155dc1556c33f13590eb99' 
  AND token = 'x5EidVrjmGMBMYuP5DvrXjJ0wJEneKcmx9PAH8JDqtI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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