SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b2938f628f973cd11e1a5c75b3fef3f88b84c125c010cb02621154199411a9c' 
  AND token = 'vtrWjht9geikYP3gV9fgn6TaRIyQPL4NdJR7WdvMrZE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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