SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88583a3f0e720a01315da81646fa4fb18b8126bf7f40e3facf455c6913e4d8f9' 
  AND token = 'TuLBVrrV/WaFjt1aYUA7RGEpPLbPha6eboNfyqMGKJM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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