SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8292333f658a78ccd6fd7f8dd156782451431a317aa73547cafb3821f3948cfe' 
  AND token = '061TqQ3xYXsja6RnHCB+Lc8qvsfhm3eZu/DPucKdOQc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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