SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0875d34f0f3ed6b408cf83c4820a1eef249e6c555b7d1b083e272894761174ea' 
  AND token = 'JcTbwHK2b/gnALEPOqOmed6Ep3lEnfRjVRhlvcKhBvk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}