SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ceccc8f062307856537e3a5712d37e8230585d01190e4716333f32c26d9b66cc' 
  AND token = 'ckYfIuQyROrHXBh/I9ym0/jhaigCqZ3NnxtLOaI6K/k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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