SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd316b9a5a0c4c0b319ffb101eee65e609936f0875791ee25e6f2f96717664ed' 
  AND token = 'qZOlpJEK+IjloKitYKGItTzh0dqEwyC5OfdPthLrwxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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