SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25031aaef83f16fe27d75bd82d705677416e8585386923b247b9e141d817c6f5' 
  AND token = 'azAvHmcCV+5eNjviClewG7r7UF8ApWwJiv2h93XoUjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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