SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cb04f060949ad2c0357ee81acae60eb1fa88caa06253c667b705ba84d6d6276' 
  AND token = 'CHT3OpwsCcgvEbl6piYsBekHXtmzZjrbE1bLEx745Jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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