SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccd79e8a9a2c8b2594965d3f67afad65d39616937a5b3c5507b1fbc450d53f2d' 
  AND token = '5sX7mxU1xEHBOWNg8+Kqjy5zUOpvFXVkI4YZFVmQJh4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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