SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c01b46e746546b48dbb014f7161b4337b9377db0c33f214df6d04726d289e0c6' 
  AND token = 'KzrwoRgvE02F2JFw83Amezgt+Zk+mBL8c+Chn2vMOJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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