SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a10dbdd7b57a5e08f8c540774529fb506a681bfabd559fcbdfc0df22f1ee70bb' 
  AND token = 'BiwWBD8lr+fnohr84lSfaK7UgnbcAEQ2jB6clg/zsbU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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