SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fa0a017f22101a413768604d8a21907659cb001e5b4cdb8f7d29d54e4874d2d' 
  AND token = 'QcW7kM5pBL9S+sUlaM5H/uTZnZ+iUhhUfnqJzijPUHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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