SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db5c854147d30c488959fe9f6407e38090035732db54601c1e03c538871f3448' 
  AND token = 'dBhYoVyMjI4p8HYeBJbLG7M7tXpB6rzpQp0uOxxd8q0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}