SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e635b684fb2bbf16f7d449615a2a17efd3de969529eccab56ac329ba86e8fb8' 
  AND token = 'dwQeFpepIgwLRqKaHrIWJdoUIiYFMRodaBcK8uqcrww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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