SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef32e62a0e2e52fa882debef6309e8b0f1c492b2a365bece0d83897b5f8f67be' 
  AND token = 'HzgX6PDGkokOI3zcthXJlxg2HZXz4PuGPdkYZm2maHI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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