SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f94f9f7a351902907cce7dde396bc9bd3af83fd023fe7ba73445f4ab33990999' 
  AND token = 'u3lhqMjMFGxXUZbsjWmsEHmlTwcx6xzlJ/ETn5D0HyA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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