SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3e3fe885e92c799daf5a975802b7065c0cb4e81e0415aa259747476b1678db49' 
  AND token = 'CK0JNOVbw0hLIHM5gZuTLQMEBMSYZXA3zKwh2pU9LrU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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