SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '215a306be336145da1397a4d3b5da67e13c10468553ac3b34ef4440e9c0ca92d' 
  AND token = 'NcAnnlwXvemqHiT8pvylisOHFKwtYAXyJCShTuOiVH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}