SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98eec1d4ae6153dccb7fe8b317f7a51576acabbbfbfba20d2ae3f7c319a6243c' 
  AND token = 'gwaDO6OaJkNWUM8Z+YY3iKwqVGc3h2VlKHdzRRczGR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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