SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a524ecefdc1ea721ebc9441ab97b77420c1ff19f900dd2209e3190c30736ad4d' 
  AND token = 'SVPip/2eMcugjZqK5MVKhFmIT4V4lgZ3xn7oQviFWLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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