SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7353cdd7e5025ef76fd1b5f2f7f5cbc80651e41c444fd8b6e77f99d87a783511' 
  AND token = 'UAASHMhRBaXREqcPkNL11M4+2GghKZcROyKkNGdyb0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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