SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a5d3e03b4b0327e166f885e9f82f7ec904032d068c7127abd638928cddd6697' 
  AND token = '+vT2ptGpt+hVXf5qo7wX3FX0r0W7zJk3cjBTlQnD4wg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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