SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4938d7f83c50e3aef77c973cd3392d8eee3c5dc20f64d8368262ab3d99f04a23' 
  AND token = 'Qt1L48xiuoGkqHE7hjv6i9p5eDEnmMP0vuN0fKRaugM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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