SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a2825e5b0c43ebd002b87e0c64d7c824741ec1082613c1bd171ed03e5417f8f' 
  AND token = 'TjmrFZhcQuoBIrviKwziVpn3vzKmfINjxrPzcvD4kqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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