SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '241b695cfd335a5925c5533b51f17f00012d3d0c60267dda7cf004ddf80f4ab9' 
  AND token = 'Xgezaclo0UboXFyKDR4WUKEnAvuRf1aFGPOtfVkzrfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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