SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67960a59aa8cc189119fe88936501e3c58bb4542442766bf82ef2ddfe60a5c33' 
  AND token = 'BLDJ6WeYALZt+V8CPNi2sAbkk9BOljv2XAa3RtuP8CM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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