SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd66341b636a783db85cdc78dd021f3b017588acc6459db5b56f286d298a95c2' 
  AND token = 'vLI8E/lJi9RV7N+vBvmZrbC2iSQUQ/kgA5zzAKhGE4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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