SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4b78114d23dd3eb87bcf93b002b0b97726d034ee198b4af0cddacbb5b3efeb1' 
  AND token = 'k3syDQA7gcGWN2yXk7/0v2pGgl/pXmOOgRddowaPDVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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