SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '580cdc8227e8e8822f6a878952d391fcc3b4cf85d04cc037f39fec438eb3dbb0' 
  AND token = 'K4U6S6RtjOc2hxDkbAWlnMQw02rfS79w8NHjJL4XWyM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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