SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ddbb6d1ff5bb998c11afbeaad7b34027eb3f95a8acdbc400767bcf5b580c442' 
  AND token = 'wjGQjy5Tk+XRClybFX/yhqLauLrWP2zknlbXjdSPWA4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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