SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7bd431048d31a661ef921a8c4a0f7c2b79215fc3f20c16aab385d35747e89f33' 
  AND token = '1vsTqa5xS+0r/FU9uVKAKOGaEQf7P8Z/HHShK2dg9iQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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