SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07846d082c9773d1a004375d8e50e2a9d509cb2f52a883c87e1f655159c047fb' 
  AND token = 'FLpt52bk6XxbINWIq41ZAngepDTJw2EPKZI2bryvcc8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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