SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b7584cbd5e44d3bcae9dd14dc1f67d023cca06c528c344649fd697b8c4b20eb5' 
  AND token = 'z6qPAhtBjMDOPD6yfSDZy6w6YVgqsr7r4/e5QUhOyJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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