Sandbox

SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '248ece2ea5cee424c8b9b7d6d04a8b6499bcc3506f50b2865dd4c42d50be4ac2' 
  AND token = 'zrqSrMSf6tHqWBS2CnBc5x0cYJKhh+FjUDpdVi9MPPM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}