SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2529e9ab55994081354b3eb330aedc6535953c8462c033e50d9f23dd043af5f0' 
  AND token = 'YjDEh9U77nVT3IZukQ1BgwDTfBQMie7lHoG722XZ8O0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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