SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3001eac42270d93f1ee6879c903195395d9a1e44f50d11407e29102689aeafbc' 
  AND token = 'pvAlDbNXo+Wi/UKLe4YMHsklPkiFhFhO4xVhcDsrhbM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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