SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d1de4a7e97927586c214658f4907efea9e53183cdc3818626a86e302259bcde' 
  AND token = 'G7hymBOEiarmT12RfoJXEbhRRCEKZYm3ZN9NlJwS/mo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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