SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '390e2c6abb8f79e0900010b5329428c812085aa5627aa6686791f81b8f525d95' 
  AND token = 'H4owAHGGXo1KsBO6jQ9K6wco7zwvHROm6W6cnSjq3o4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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