SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd8b56c780081d5d07cdad4d8ffd99fb2849c93e9f74d676981194a6444344fa9' 
  AND token = 'fGC/L0byGSCOweYs1r5ibAjVXGspUROKfVBbw4/WDu4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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