SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2e0f4cf799a4d8ff68372eda7901ecd90a55f5e4be16063f688388942d3fc887' 
  AND token = 'zx+sUCpcflvI6Yu89i5xpHvdMK5uY8M/95m7dGZIBwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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