SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea4fc40654ec98ff14ea3656604b267eb3594b71493158953e5c9399959707c8' 
  AND token = '1rqxQPSjGVYqN0C7UDgQfC8+hhffNyqyXUbiTFMluW4=' 
  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"
    }
  }
}