SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '794cd7117915b74ea7136ce1bb48e898486ea7764ba219bd487e529f92d9d3dd' 
  AND token = '0FmwdQ8zRTXnaZ0Ep+tZUC9f2JdNPjDJjEdXMCHfpvE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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