SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d416caae84aaaf7fd7dab6bcaf89b844d5fc50295bb8cc9e03880a0fc05364b' 
  AND token = 'F67vSohIvq4n1tiS/d5X/XiJG9K3geYMT+vJODPnH5w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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