SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '874b8c95ed304ec2c8c0a37aa89aff17d15107e6ae76fde438d8f7b8f2cdc590' 
  AND token = 'O3/0ARMTkqxRYMnorNPxfdAO32oBWbag5HHLwkjhfMI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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