SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6129691a638e3a154f62e8a4abbc7a85cbc22895265459f5a3823a30b948cbb7' 
  AND token = 'BgjT8/YuRMaxFvj625+WyYGvByEY3GQQrLs0BaOcytQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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