SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d5a22cf574a84fed981a2db8ade7848a555606ea8b104a74fcde36281ac30fa' 
  AND token = 'rYmM3nFfBEqAQ+dBCOF1U9XgeUM896FSAuzatRyGWpA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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