SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7adf490c076f143d6e0bdbdc89988b01877f1ac41f42fa8d0d950a6a3bf5bd87' 
  AND token = 'xSpaInVBW6sntTwGXp4XkVnPUr2tha+MhHxx1YzwtR8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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