SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d787c789fb5f71ec71353947c397f68f6053868b23e0fb968b143a816ce8e08' 
  AND token = 'T77yFF4o/U4SEh2znUb8XIPMp1AmcNYFDgpJ3vpBLwo=' 
  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"
    }
  }
}