SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8df9dc4b536cdcfd48a0f8cb51acb2126c36c36f95f34b7119956fa65fc3f887' 
  AND token = 'Gvjaw4/dsgIpvx523eOakutwzypjpBy0xtQdqqSNVP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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