SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b38370682956af36bec22822850fcdf30476cf67edf9c34320ae106fbf05cd7' 
  AND token = 'P2APLjTdYPUkHskoH7UhGPPE1tyCS7VuAXFc+E8Wsjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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