SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ecd7e277ae7d675b60f24e60b2ab9ce89ec2c61f80161dd4d3f805fdfb871dd' 
  AND token = 'IOIfyvrmtuoPuC9GrdrUqlNv8dJs9b17wSHwgpM3T4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}