SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec8bd7204d199b807ece4e695303e8f0864d6b36b7e9261c11e5db846672e64a' 
  AND token = '2+nahLKlt8U0g8qpCtAXetl8YqlpxSrSaUSsgXFFwsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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