SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '832b561515754232684dee9aae4975ab2fb845bbb16ea058959e543983a6e5c5' 
  AND token = 'gk4rbvQX4HshbUvwy8UpQSRHl1sHV8U8dm8u04BIjC0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}