SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58ea5fd588437dcfab2ea80480f124582c04b43971703bc3cd94628bc2e61fab' 
  AND token = '1eZvEahbqOQwpo8M0SNcIcQCkP12T5xNqzG52TduGE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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