SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2e5b265410ed00cdfae3fd7bc99ebeadea17d28249ea35aed296a7353dba775' 
  AND token = 'wJt66AVDc28YLmbInjr//2Sh5YoC1HIpcr8tZpd8e7c=' 
  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"
    }
  }
}