SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a0de04a1dc4c6008a2ea5630dd4b198921fc63c90258c387747264717a3e127' 
  AND token = 'vPFyYPuVW+oolrHvKJNGFp4kjVqcoI1yDVem6U19G98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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