SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb35ffd0d570106c66417ff950169abd91f4917b95087bd95afe90fc545558f3' 
  AND token = 'Oe06cQuHTnB/nl2Z+6qrW4JLK8u5HcQNiIbBMllyQ+U=' 
  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"
    }
  }
}