SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c67f2ff609f68c87733ff5cdacd757417e87c07de163dc48ce83030df593e73' 
  AND token = 'cxpQYPkv7ICfku6tJmCBd/PhTrsCnlvJnKg7oLkHUjw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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