SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4903def2825668ee162d60f8335917b9fee4f0b3fdb23b27e9fcd8617e71c231' 
  AND token = 'nouZv9p4Xdue3bLOIsjcgPlZgSwcqqTQWVAbVKaQApI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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