SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '463ac601dc6677f10c5df7fb50ea82867f4f0860d3b062f3be2feb392ff15149' 
  AND token = 'LXvca9iXJ5KTxPQH00A9bOMpbRGeVqYK6zNPvFujnkw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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