SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2203dfa81ba6afccc4b3887c963d1c91553bc38fbf93a32754067a599701e922' 
  AND token = '/0jX+KK/42fjEgjdXO0eWOThroCIbq15wN43OFu1Wh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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