SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8187ea7f1be8a0839ddfb2538ddb50b8a1a975f5e128e07a3e76621d4642d9d7' 
  AND token = 'tGo0xPaOS7sxUuR0bNObMlNEXmxX5XMcF60/SVoXVkQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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