SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '136bcbcc0e5b652dfe5beab76a700c2fe315f3a9f9109d78edf3b1e9e265ce0f' 
  AND token = 'K9nhH16bRC34luRapp39n6tU6d1WQRbYfdukB/5a3Tc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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