SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba26b3a89a2c9ba6da67d160d40809a900865baf8b9146180d0255d3f78bb688' 
  AND token = 'JojPygGpttI6cMfCSYz76CK7GCB/edOWmVllqzzXK74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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