SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f4b4e9c8adb1453184bd618a393327d9975ca7791304660b4b73e8f93dcf6f9d' 
  AND token = 'Uvow03ND2ca8rkGj+kKJce9SSWVH8U1geFbIZBBbnPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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