SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88dbeb293a79d29c67cc1517bf957e019222db6567c02625a1446f5ac5f8e50a' 
  AND token = 'vunZL+TZFosz85R0Pnr89YXZVZBPXw6Fpdn2Gkciodo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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